Value Village ／ Beauty
This answer is a draft. It stays unpublished until legal review and source verification are complete.
The brown patches lumped together as "dark spots" (シミ, shimi) in Japan come in at least five kinds, each with a different cause and a different answer. Some respond to brightening (bihaku, 美白) cosmetics; some hardly change with any cosmetic; some get darker with the wrong care. This article gives the signs for telling them apart and a realistic approach to each.
| Kind | Appearance | Main cause | What cosmetics can do | What a dermatologist can do |
|---|---|---|---|---|
| Solar lentigo (老人性色素斑, 日光黒子) | Sharp-edged brown patches, a few mm to a few cm. Cheeks, temples, backs of hands. The most common | Accumulated UV (rises from the 40s but appears in the 20s too) | Prevention (sunscreen). Existing spots hardly fade | Q-switched laser, IPL light therapy can remove them. Self-pay (not covered by health insurance) |
| Melasma (肝斑) | Symmetrical, hazy light-brown patches on the cheekbones, also forehead and around the mouth | Female hormones, friction, UV. Women in their 30s–50s; pregnancy and the pill make it likelier. May fade after menopause | No rubbing, UV protection, brightening actives (e.g. tranexamic acid) | Oral tranexamic acid (usually self-pay), topicals. Strong lasers can make it worse and are often contraindicated |
| Post-inflammatory hyperpigmentation | Brown marks left by acne, insect bites, burns, rashes, friction | Inflammation increases melanin | UV protection and brightening actives help. Fades naturally over several months to a year | Topicals or laser if needed |
| Freckles (そばかす, 雀卵斑) | Small brown dots scattered over the nose and cheeks, from childhood | Hereditary. UV darkens them | UV protection so they do not darken | Laser can lighten them |
| Seborrhoeic keratosis (脂漏性角化症, "age warts") | Slightly raised, rough brown-to-black spots | Ageing, UV | Cosmetics do nothing | Liquid nitrogen, laser, excision (some covered by health insurance) |
| ADM (acquired dermal melanocytosis) | Symmetrical grey-to-bluish patches on the cheeks | Melanocytes in the dermis | Cosmetics do nothing | Laser (several sessions) |
[Verify] Check the classification of dark spots and the procedures against Japanese Dermatological Association and Japanese Society of Aesthetic Dermatology material; costs are typical clinic figures. Check the permitted claims for brightening actives against MHLW quasi-drug approval information.
The approved claim is "prevents", and solar lentigo and seborrhoeic keratosis hardly change with cosmetics. Prevention and support for post-inflammatory marks is the realistic range.
Melasma can worsen under a strong laser, so diagnosis comes first. Each kind needs a different approach.
Friction is one of the classic causes of melasma and darkening getting worse. Do not rub the face.
Solar lentigo comes from UV accumulated over the whole year, and UV is present in winter and on cloudy days. The daily habit is the core of prevention.
Options for prevention and medical care keep growing. But a spot that grows fast, has an irregular shape or bleeds may be skin cancer — do not leave it; see a dermatologist.
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https://www.dermatol.or.jp/qa/
https://www.dermatol.or.jp/uploads/uploads/files/guideline/
https://www.mhlw.go.jp/
⚠️ Editorial note: the source URLs above were identified by search. Our working environment cannot reach go.jp domains, so the contents have not been checked against the text. Verify every source before publication and record who checked it and when.
What we share here are ideas and everyday practices passed down among people living in Japan, together with general information drawn from public sources. They are not official recommendations, and they are not professional instruction. Practices vary between households and regions.
This is general information. Results vary from person to person and depend on your own conditions and surroundings.
Please decide for yourself, using your own judgement, whether any of this suits your situation. We cannot accept responsibility for any damage, loss or injury arising from following this article.
Cosmetics are not medicines and are not meant to diagnose, heal or prevent any condition. If your skin reacts, stop using the product and see a dermatologist.
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